Two-piece or multi-piece ball bats were designed to reduce shock transmitted to a batter's hands during an “off-center,” or “non-sweet spot,” hit. A two-piece ball bat including a handle section joined to a barrel section via an elastomeric isolation union, for example, is described in U.S. Pat. No. 5,593,158, which is incorporated herein by reference. The elastomeric isolation union is located between, and bonded to, an outer surface of the handle section and an inner surface of the barrel section. The incorporation of an elastomeric isolation union at an axial location above where a batter typically grips the ball bat provides significant attenuation of shock waves that result from off-center hits, and that would otherwise be transmitted to the batter's hands.
While existing two-piece ball bats have been successful at attenuating shock, most two-piece bat designs have focused strictly on this shock attenuation feature. The two-piece bat concept, however, provides an opportunity to tailor several additional features of a ball bat, such as the feel and flexibility of the ball bat.